A container treatment plant known generally from the prior art has for example a portion for heating the containers, a portion for inflating and stretching the containers, a portion for sterilizing the containers and a portion for closing the containers.
In this case the portion or the plant for closing the containers comprises for example at least one apparatus for closing the containers which has at least one closure head for applying the closure caps to the containers, a movement device for transferring a rotational and a translational movement of a motor to the closure head and a clean room in which the containers are moved during the procedure.
A closure head for an automatic lid application machine is described for example in EP 1 905 728 B1, which has a support, a turning shaft and a lid-gripping element. The support has mounted on it a rotatable turning shaft which is surrounded by a sleeve which forms a chamber which is sealed off around the turning shaft and which is filled with a disinfection agent, the sleeve being stationary with respect to the support. The chamber is closed by two mechanical seals which in each case have a stationary part and a turning part. The sleeve itself extends through an opening in an upper stationary plate and has on its external periphery a bellows, the upper end of which is mounted on the stationary plate and the lower end of which is mounted on the sleeve. In addition, the chamber is connected to an inlet opening and an outlet opening for the disinfection agent, the openings being situated above the stationary plate and thus in the non-sterile area. In this case sealing the non-sterile area off from a sterile area by means of an hydraulic seal is carried out only by way of the sleeve, which must additionally have a seal in the region of the plate which it passes through. Accordingly, sealing systems provided in addition to a hydraulic seal are required.
DE 10 2008 034 389 A1 describes inter alia a closure machine for the closure of bottles, which has a functional element which has a wall separating a sterile room from a non-sterile room and with an hydraulic seal which permits a relative movement of the functional element with respect to the wall. The closure machine thus comprises a rotor which is capable of being driven and on the periphery of which is arranged an annular sterile room which surrounds the vertical axis of the machine concentrically and which is formed inside a casing and is demarcated from the non-sterile room by a plurality of walls.
In this case some walls are provided on the rotor, which rotate with the latter and other walls are provided on a machine frame, which do not rotate with the rotor. A hydraulic seal is arranged between these walls. The closure stations arranged in the periphery of the rotor have a closure tool which has a drive arranged outside the sterile room and a spindle which is arranged in part outside the sterile room and extends through the hydraulic seal or the siphon seal as far as the sterile room. This hydraulic seal has a highly complex design outside the first wall regions.
In addition, DE 10 2008 056 242 A1 describes a closure apparatus for containers, which has a closure head for applying the closures to the containers, which closure head is arranged inside a sterile room and performs a translational and a rotational movement. These reciprocating and rotational movements are transmitted to the closure head by a movement device which is arranged in part outside the sterile room and which produces the movement itself or is moved by a drive element arranged outside the sterile room. The sterile room is bounded by a first wall and has an annular channel into which the first wall projects. This annular channel is movable with respect to the first wall and is filled with a liquid and thus forms a so-called surge chamber together with the first wall.
This surge chamber seals the non-sterile area off from the sterile area. The movement device extends through this surge chamber from the non-sterile area into the sterile room. To this end a cylindrical body through which the movement device extends is arranged in the annular channel and is connected to it in a fixed manner. In addition, the movement device has a cylindrical body which is arranged on it and the peripheral wall of which projects into the liquid independently of the position of the movement element. In order to seal the clean room off from the non-clean room, this apparatus accordingly requires bodies which are designed in a complicated manner and which are arranged one in the other in such a way that sealing by means of a surge chamber can take place even in the case of a translational or rotational movement of the movement device.
Accordingly, it may be desirable to make available an apparatus for the closure of containers, which despite a simple structural design permits an adequate sealing of the clean room off from the non-clean room even during the movement of the movement device in the rotational and the translational directions and, as a result, is economical to produce and simple to assemble and maintain.